Convert PDF to PNG in Multi-thread mode using C# and .NET

Complete code

using System;
using System.IO;
using System.Collections.Generic;
using System.Threading;
using SautinSoft;

namespace Sample
    class Sample
        static void Main(string[] args)
        public class TArgument
            public string PdfFile { get; set; }
            public int PageNumber { get; set; }
        public static void ConvertPdfToPngInThread()
            string pdfs = Path.GetFullPath(@"..\..\..");
            string[] files = Directory.GetFiles(pdfs, "*.pdf");

            List<Thread> threads = new List<Thread>();
            for (int i = 0; i < files.Length; i++)
                TArgument targ = new TArgument()
                    PdfFile = files[i],
                    PageNumber = 1

                var t = new Thread((a) => ConvertToPng(a));

            foreach (var thread in threads)

        public static void ConvertToPng(object targ)
            TArgument targum = (TArgument)targ;
            string pdfFile = targum.PdfFile;
            int page = targum.PageNumber;

            string pngFile = Path.GetFileNameWithoutExtension(pdfFile) + ".png";
                                  // Get your free 30-day key here:   
            SautinSoft.PdfFocus f = new SautinSoft.PdfFocus();

            f.ImageOptions.ImageFormat = PdfFocus.CImageOptions.ImageFormats.Png;
            f.ImageOptions.Dpi = 300;


            bool done = false;

            if (f.PageCount > 0)
                if (page >= f.PageCount)
                    page = 1;

                if (f.ToImage(pngFile, page) == 0)
                    done = true;

            if (done)
                Console.WriteLine("{0}\t - Done!", Path.GetFileName(pdfFile));
                System.Diagnostics.Process.Start(new System.Diagnostics.ProcessStartInfo(pngFile) { UseShellExecute = true });
                Console.WriteLine("{0}\t - Error!", Path.GetFileName(pdfFile));


Option Infer On

Imports Microsoft.VisualBasic
Imports System
Imports System.IO
Imports System.Collections.Generic
Imports System.Threading
Imports SautinSoft

Namespace Sample
	Friend Class Sample
		Shared Sub Main(ByVal args() As String)
		End Sub
		Public Class TArgument
			Public Property PdfFile() As String
			Public Property PageNumber() As Integer
		End Class
		Public Shared Sub ConvertPdfToPngInThread()
			Dim pdfs As String = Path.GetFullPath("..\..\..")
			Dim files() As String = Directory.GetFiles(pdfs, "*.pdf")

			Dim threads As New List(Of Thread)()
			For i As Integer = 0 To files.Length - 1
				Dim targ As New TArgument() With {
					.PdfFile = files(i),
					.PageNumber = 1

				Dim t = New Thread(Sub(a) ConvertToPng(a))
			Next i

			For Each thread In threads
			Next thread
		End Sub

		Public Shared Sub ConvertToPng(ByVal targ As Object)
			Dim targum As TArgument = DirectCast(targ, TArgument)
			Dim pdfFile As String = targum.PdfFile
			Dim page As Integer = targum.PageNumber

			Dim pngFile As String = Path.GetFileNameWithoutExtension(pdfFile) & ".png"

								  ' Get your free 30-day key here:   

			Dim f As New SautinSoft.PdfFocus()

			f.ImageOptions.ImageFormat = PdfFocus.CImageOptions.ImageFormats.Png
			f.ImageOptions.Dpi = 300


			Dim done As Boolean = False

			If f.PageCount > 0 Then
				If page >= f.PageCount Then
					page = 1
				End If

				If f.ToImage(pngFile, page) = 0 Then
					done = True
				End If
			End If

			If done Then
				Console.WriteLine("{0}" & vbTab & " - Done!", Path.GetFileName(pdfFile))
				System.Diagnostics.Process.Start(New System.Diagnostics.ProcessStartInfo(pngFile) With {.UseShellExecute = True})
				Console.WriteLine("{0}" & vbTab & " - Error!", Path.GetFileName(pdfFile))
			End If
		End Sub
	End Class
End Namespace


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